@fweinb Have you noticed that the header changes length when record is enabled? On the GH4 the header becomes 16 bytes longer (16 extra bytes inserted after byte 46).

@mjas and @Rambalac header length changes depending on the mode (P, A, S, M, Auto) you're in, I don't think the lens changes anything. I think A, S, M are the same, and P and Auto are shorter.

Didn't play with GH4, and didn't look at this for a loooong time, but it's what I remember.

@lenuisible @Rambalac I've seen that the header length changes, but as far as I can see the first 46 bytes seem to be the same (judging from GH4 and G80 headers). However I can't see anything in those first 46 bytes that indicates what comes directly after.

@Rambalac Sure. Do you have a link? I could only find Panasonic RAW decoding code online. :)

@Rambalac Thanks!

Seen this? https://itunes.apple.com/gb/app/gmonitor/id1219955645?mt=8

@lenuisible Oh, ok I added that for better Image App like behavior, it will be available in next update together with LUTs . Thanks

@Rambalac I've checked now with G80 and GH5, and the camera seems to repeat

http://Cam_IP@/cam.cgi?mode=accctrl&type=req_acc&value=4D454930-0100-1000-8001-020D0090325B&value2=GT-I9300

Where value = device_id (can be really anything), and value2 = <arbitrary name>

The Pana app keeps polling the above command, and the camera keeps answering ok_under_research,etc,etc,etc (etc is just more info) until you've accepted the connection on the camera. Once accepter, the camera will reply with a plain ok,etc,etc,etc.

After that I've witnessed both cameras be sent

http://Cam_IP@/cam.cgi?mode=setsetting&type=device_name&value=GT-I9300

And after that it seems like the procedure is the same.

@Rambalac Indeed a very unnecessary difference ...

Sorry for hijacking this thread, but the last posts relate directly to what I'm interested in.

I've been developing a follow-focus Android app for my G85 over the last weeks and just published an early access version. The idea is to use your phone to remote control servo-lenses such as the kit lens. While the the speed of the follow-focus is very limited, it might be good enough for certain setups.

However, I would like to figure potential issues with other popular models such as the GH4 before I post about it elsewhere.

I have three questions:

First, does anyone know what happens if you send the access control command (and the set device command) to older models?

My untested code assumes that these cameras will respond with either err_non_support, err_param, or HTTP code 404.

Second, is cam.cgi?mode=getinfo&type=capability a recent addition or safe to use with older models?

@Rambalac You avoid the first calls entirely for models that don't support them and I could not find the capabilities call in your code. Is there a particular reason?

Finally, is there a way to get the current focus without sending a focus change command?

I have found nothing of that sort in the HTTP data. But I haven't touched the video stream headers yet. @fweinb Do you see a chance something like that is hidden in the fields you could not identify yet?

Any help is appreciated. If you need something to be tested with a G85 (actually, it is a G81), let me know.

The code of my app is available here (including a getting started guide):

https://bitbucket.org/jimknopf/fokoid/overview

Play Store link (Early Access):

https://play.google.com/store/apps/details?id=com.gmail.fokoidapp&hl=en

(you can also find a copy of the APK on Bitbucket)

@Rambalac Thanks for the information! I am checking cam.cgi?mode=getinfo&type=capability for the tele-fast and wide-fast commands. Furthermore, I check whether oneshot_af_enable is listed as spec. But to be honest, I am not sure whether any of this is necessary.

By the way, I forgot to mention that my app includes a report function that goes through all command one-by-one and records the responses. So if anyone has an Android device (5.0 or newer) and some time to kill…

@Rambalac That's my guess. The AF is not that important to me, but knowing whether the fast focus change commands work is. Therefore, the check at the beginning.

I only have access to a G81, so no, I don't know about cameras not supporting it. I just assumed that there is a reason why some commands are listed explicitly, while others are not.

Do you know the capabilities command from your GH3 and GH4? That would already answer my first question.

I had no success with sniffers installed on my phone – which one are you using? So far I have used macOS's built in sniffer to record the traffic between the camera and the phone. Then analyzed the data in Wireshark.

The report function of my app is of course much more primitive. All it does is to save the responses of the 11 commands it goes through and then allows to send the data via email. In particular, the app itself is not phoning home.

@Rambalac OK, then I will remove it from the connection procedure. Thanks!